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Boxes of Cheerios cereal, made by General Mills, sit on the shelf at a grocery store September 23, 2009 in Berkeley, California.
General Mills made a big announcement recently.
Cheerios is going GMO free. Now, if you know something about genetically modified crops, this may sound odd. Cheerios are mostly made of oats - a crop that isn't available as a GMO.
To find out what this announcement really means, we turn now to Marion Nestle, a professor of nutrition, food studies and public health at New York University.